A drawing machine that determines a winning-object in a plurality of drawing-objects is widely utilized in a wide range of fields. For example, a bingo game machine in Patent Document 1 has been known as a game apparatus utilizing the drawing machine. With this bingo game machine, a bingo card image (an array image) arrayed in a square matrix consisting of 5 by 5 rows, in which a number image (a drawing-object image) is disposed by an array unique to each player, is displayed in a displaying unit set up for each player. After that, a winning number (winning-object) is determined from twenty-five numbers (drawing-objects) from “1” through “25” by a drawing machine, and display patterns of winning numbers and numbers other than the winning numbers are made different from each other in the bingo card images of the respective players. By repeating the above operation by a predetermined number of times, when all the numbers in any one of the longitudinal direction, the horizontal direction and the diagonal direction are drawn on the bingo card image, BINGO is established, and allotment is paid to the player.
In the drawing machine such as utilized in the bingo game machine, it is important that a participant of drawing has a impression like a drawing is carried out fairly whether or not the drawing is actually carried out fairly. Therefore, the bingo game machine described in Patent Document 1 utilizes a drawing machine carrying out so-called physical drawing. In detail, the drawing machine used in the bingo game machine is composed of a supply hole of a ball, one revolution body having a surface portion on which the ball rolls, a collecting unit provided with a plurality of pockets for collecting the ball. The revolution body is rotated on a fixed plane by a revolution driving mechanism. The revolution body makes the ball supplied from the supply hole roll irregularly on the surface portion and spring out. The twenty-four pockets are provided with a periphery of the revolution body along circumferential direction. Therefore, the ball rolling on the revolution body along circumferential direction enters into either pocket and is collected. Either of number “1” through “25” is allotted to the each pocket respectively, a number allotted to the pocket into which the ball has been entered is determined as the winning-object. According to the drawing machine carrying out thus physical drawing, since participants of drawing can understand definitely a process of the drawing, it is possible to give the participants of drawing an impression like the drawing is carried out fairly.
However, in the drawing machine carrying out thus physical drawing, there is a defect in that degree of variation when a winning-probability of each of the drawing-objects is changed is low.
That is, in an example of the drawing machine described in Patent Document 1, for example, if a size of the pockets is changed by using driving mechanism or a number allotted to the pockets is changed, it is possible to change the winning-probability of each of the drawing-objects. However, the size and the allocable number of the pocket are restricted physically. Therefore, in a restricted range, it is necessary to change the winning-probability of each of the drawing-objects, whereby a degree of variation for changing the winning-probability is low.
On the other hand, conventionally, a drawing machine carrying out so-called computer drawing has been known, by which winning-objects are determined by executing a drawing program in accordance with a winning-probability of each of drawing-objects determined by winning-probability data. In the drawing machine carrying out thus computer drawing, since the winning-probability of each drawing-object is changed freely by changing the winning-probability data, a degree of variation for changing the winning-probability is high.    Patent Document 1: Japanese Published Unexamined Patent Application No. 2001-161889